Elevatable tops or canopies for pickup truck cargo boxes are known. Some examples of the prior art are contained in U.S. Pat. Nos. 3,155,423; 3,447,830 and 3,765,716. These prior art structures have not been widely accepted for a number of reasons. Among the more important reasons working against commercial acceptance are excessive cost of manufacturing and installation and unduly complex operating mechanisms. Some of the prior art camper top operating mechanisms involve scissor-type linkages which can be hazardous to users. A further drawback of known prior art structures is the necessity for drilling, cutting or otherwise altering the pickup truck cargo box when installing the elevatable top. This promotes rusting and lessens the longevity of the cargo box.
The general objective of the present invention is to overcome the above and other drawbacks of the prior art through the provision of a pickup truck cargo box top which is supported and operated by a system of power-operated vertical axis screw jacks installed in existing side board mounts of the cargo box. The arrangement is highly simplified, reliable in operation and eliminates the necessity for drilling or otherwise cutting the metal cargo box of the pickup truck, thereby preventing any acceleration of rusting as a result of utilizing the invention.
Another object of the invention is to provide a lift top for pickup truck cargo boxes which furnishes security in that the top can only be operated while the truck ignition key is in place and the control switch for the motor-driven screw jacks is turned on. This security eliminates the need for costly built-in tool boxes in pickup truck cargo beds which are primarily designed for security reasons.
Still another object of the invention is to provide a lift top for pickup truck cargo boxes which is equipped with pull-down side curtains, facilitating conversion of the vehicle to a true recreational vehicle.
Other features and advantages of the invention will become apparent during the course of the following detailed description.